Antibodies to human heat shock protein 60, hypertension and dyslipidemia. A study of joint effects on coronary risk

OBJECTIVE: High IgA-class (but not IgG-class) Anti-Heat-shock-protein 60 antibody level is a predictor of coronary risk in dyslipidemic middle-aged men. In this paper we studied the joint effects of high Anti-Hsp60-antibody level and the classical coronary risk factors. METHODS: We used nested case-control design and logistic regression analyses. The cases consisted of 233 middle-aged men with myocardial infarction or coronary death during 8.5-year follow-up in Helsinki Heart Study, a coronary primary prevention study with gemfibrozil. The controls were subjects without coronary events, matched for drug treatment and the geographical area. RESULTS: The relative coronary risks (Odds Ratios (ORs); 95% confidence interval) were 1.41 (0.96-2.05) for high IgA-class Anti-Hsp60 antibody level and 1.98 (1.35-2.90) for hypertension, defined as mean arterial pressure >114 mmHg. With simultaneous occurrence of high Anti-Hsp60 antibody level and hypertension, the ORs were 2.32 (1.26-4.27) for systolic and 2.99 (1.63-5.48) for diastolic hypertension. Similar patterns of joint effects were found between high Anti-Hsp60 antibody and lipoprotein cholesterol levels as well as antibodies against oxidized low-density lipoprotein. CONCLUSIONS: Our results suggest that, while high IgA-class Anti-Hsp60 antibody level predicts coronary risk, the effect is modest without simultaneous occurrence of other classical risk factors.